WBJEE 2019 Physics Solved Paper

Given, Power (P) = constant
Kinetic Energy (KE)=‌

1

2

mv2
We know that, P=‌

KE

∆t

⇒P=‌

mv2

2

∵ P = constant
Hence, velocity of the body v∝√t....(i)
As, Velocity v=‌

ds

dt

.....(ii)
From Eqs. (i) and (ii), we get
So,

ds

dt

∝√t
Integrating the above equation w.r.t. time (t),
∫‌

ds

dt

∝∫√t
we get, displacement of the body s∝t3∕2
∵ Displacement s=at3/2, where a is constant.